地面堆载引起桩基负摩擦力的分布特性分析  

DISTRIBUTION CHARACTRISTICS OF NEGATIVE PILE FRICTION CAUSED BY SURCHARGE LOADING

作　　者：高昂[1] 宋二祥[1] 

机构地区：[1]清华大学土木工程系,北京100084

出　　处：《建筑技术》2014年第9期824-828,共5页Architecture Technology

摘　　要：针对桩侧堆载的分布范围,桩顶加载大小,桩顶加载与桩侧堆载的施加次序等因素,通过有限元建模分析的方法,探讨各因素对桩侧摩擦力分布及桩基极限承载力的影响。结果表明随着侧堆载分布范围的减小和桩顶加载值的增加,中性点位置上升,下拉力减小;桩顶加载与桩侧堆载的施加次序对侧摩擦力的分布有较大影响;只考虑土对桩的支撑作用不考虑桩身材料强度时,堆载作用下桩基极限承载力非但不降低反而提高。This paper discusses the pile negative friction distribution and the ultimate bearing capacity,through finite element analyses,considering the distribution range of surcharge loading,the amount of pile cap loading and the sequence of pile cap loading and surcharge loading.The results show that the neutral point rises and the downdrag force reduces with decrease of the surcharge loading range and increase of pile caploading; the sequence of pile cap loading and surcharge loading has great influence on the friction distribution ;the ultimate pile bearing capacity with negative friction caused by surcharge loading does not decrease,but increases instead if the bearing capacity is determined by the soil supporting the pile without considering the material strength of the pile.

关 键 词：负摩擦力 桩侧堆载 桩顶加载 加载次序 极限承载力 

分 类 号：TU470[建筑科学—结构工程]